@block-backup
Start a point-in-time copy of a block device to a new destination.
@device: the name of the device whose writes should be mirrored.
@target: the target of the new image. If the file exists, or if it
is a device, the existing file/device will be used as the new
destination. If it does not exist, a new file will be created.
@format: #optional the format of the new destination, default is to
probe if @mode is 'existing', else the format of the source
@mode: #optional whether and how QEMU should create a new image, default is
'absolute-paths'.
@speed: #optional the maximum speed, in bytes per second
Returns: nothing on success
If @device is not a valid block device, DeviceNotFound
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
blockdev.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
qapi-schema.json | 28 +++++++++++++++++
qmp-commands.hx | 6 ++++
3 files changed, 126 insertions(+)
diff --git a/blockdev.c b/blockdev.c
index 8a1652b..521d999 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1279,6 +1279,98 @@ void qmp_block_commit(const char *device,
drive_get_ref(drive_get_by_blockdev(bs));
}
+void qmp_block_backup(const char *device, const char *target,
+ bool has_format, const char *format,
+ bool has_mode, enum NewImageMode mode,
+ bool has_speed, int64_t speed,
+ Error **errp)
+{
+ BlockDriverState *bs;
+ BlockDriverState *target_bs;
+ BlockDriver *proto_drv;
+ BlockDriver *drv = NULL;
+ Error *local_err = NULL;
+ int flags;
+ uint64_t size;
+ int ret;
+
+ if (!has_speed) {
+ speed = 0;
+ }
+ if (!has_mode) {
+ mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
+ }
+
+ bs = bdrv_find(device);
+ if (!bs) {
+ error_set(errp, QERR_DEVICE_NOT_FOUND, device);
+ return;
+ }
+
+ if (!bdrv_is_inserted(bs)) {
+ error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
+ return;
+ }
+
+ if (!has_format) {
+ format = mode == NEW_IMAGE_MODE_EXISTING ? NULL : bs->drv->format_name;
+ }
+ if (format) {
+ drv = bdrv_find_format(format);
+ if (!drv) {
+ error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
+ return;
+ }
+ }
+
+ if (bdrv_in_use(bs)) {
+ error_set(errp, QERR_DEVICE_IN_USE, device);
+ return;
+ }
+
+ flags = bs->open_flags | BDRV_O_RDWR;
+
+ proto_drv = bdrv_find_protocol(target);
+ if (!proto_drv) {
+ error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
+ return;
+ }
+
+ bdrv_get_geometry(bs, &size);
+ size *= 512;
+ if (mode != NEW_IMAGE_MODE_EXISTING) {
+ assert(format && drv);
+ bdrv_img_create(target, format,
+ NULL, NULL, NULL, size, flags, &local_err, false);
+ }
+
+ if (error_is_set(&local_err)) {
+ error_propagate(errp, local_err);
+ return;
+ }
+
+ target_bs = bdrv_new("");
+ ret = bdrv_open(target_bs, target, NULL, flags, drv);
+
+ if (ret < 0) {
+ bdrv_delete(target_bs);
+ error_set(errp, QERR_OPEN_FILE_FAILED, target);
+ return;
+ }
+
+ backup_start(bs, target_bs, speed, block_job_cb, bs, &local_err);
+ if (local_err != NULL) {
+ bdrv_delete(target_bs);
+ error_propagate(errp, local_err);
+ return;
+ }
+
+ /* Grab a reference so hotplug does not delete the BlockDriverState from
+ * underneath us.
+ */
+ drive_get_ref(drive_get_by_blockdev(bs));
+}
+
#define DEFAULT_MIRROR_BUF_SIZE (10 << 20)
void qmp_drive_mirror(const char *device, const char *target,
diff --git a/qapi-schema.json b/qapi-schema.json
index 751d3c2..903d2a5 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1715,6 +1715,34 @@
'*speed': 'int' } }
##
+# @block-backup
+#
+# Start a point-in-time copy of a block device to a new destination.
+#
+# @device: the name of the device whose writes should be mirrored.
+#
+# @target: the target of the new image. If the file exists, or if it
+# is a device, the existing file/device will be used as the new
+# destination. If it does not exist, a new file will be created.
+#
+# @format: #optional the format of the new destination, default is to
+# probe if @mode is 'existing', else the format of the source
+#
+# @mode: #optional whether and how QEMU should create a new image, default is
+# 'absolute-paths'.
+#
+# @speed: #optional the maximum speed, in bytes per second
+#
+# Returns: nothing on success
+# If @device is not a valid block device, DeviceNotFound
+#
+# Since 1.5
+##
+{ 'command': 'block-backup',
+ 'data': { 'device': 'str', 'target': 'str', '*format': 'str',
+ '*mode': 'NewImageMode', '*speed': 'int' } }
+
+##
# @drive-mirror
#
# Start mirroring a block device's writes to a new destination.
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 4d65422..ce73e44 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -889,6 +889,12 @@ EQMP
},
{
+ .name = "block-backup",
+ .args_type = "device:B,target:s,speed:i?,mode:s?,format:s?",
+ .mhandler.cmd_new = qmp_marshal_input_block_backup,
+ },
+
+ {
.name = "block-job-set-speed",
.args_type = "device:B,speed:o",
.mhandler.cmd_new = qmp_marshal_input_block_job_set_speed,
--
1.8.1.4
